The present invention is directed to antimicrobial implants and methods of manufacturing the same.
It has become common to treat a variety of medical conditions by introducing an implantable medical device partly or completely into the human body. For example, orthopedic devices are commonly inserted into joints such as the knee, spine, shoulder and the like. Additional orthopedic devices are often implanted adjacent bone such as metal plates during fracture repair and spinal rods for the re-alignment of the spine. Many other implants are used for implantation into the esophagus, trachea, colon, biliary tract, urinary tract, vascular system or other locations within a human or even a veterinarian patient.
One disadvantage associated with implantable medical devices is microbial adhesion. Microbial adhesion occurs when unwanted parasites adhere to the orthopedic implant either during implantation or afterwards.
Microbial adhesion to the surface of an implant device that eventually lead to biomaterials-related infections is a well recognized complication of implant materials and devices. Once adhesion has occurred, proliferation of the microbial agents leads to the development of a biofilm, which is unsusceptible to most therapeutic agents at achievable concentrations. Thus, the course of microbial infection involves three major steps: microbial adhesion; microbial proliferation; and formation of a bacterial bio-film.
Unfortunately, only a few materials, as for instance, gold, silver or copper, show toxicity against microorganisms and biofilm formation. Gold, silver and copper ions are believed to have broad spectrum anti-microbial activity. Of all the metal ions, silver exhibits a high toxicity for microorganisms and is one of the least toxic to animal cells. Still, silver ion concentrations higher than 10 mg/l may be toxic to certain human cells.
It has therefore been known in the art to apply an antimicrobial coating that includes metal ions and specifically silver at low concentrations to combat microbial adhesion.
Still, additional antimicrobial compositions and different ways for incorporating the antimicrobial with orthopedic implants are required.